Sir Oliver Joseph Lodge, (born June 12, 1851, Penkhull, Staffordshire, Eng.—died Aug. 22, 1940, Lake, near Salisbury, Wiltshire) British physicist who perfected the coherer, a radio-wave detector and the heart of the early radiotelegraph receiver.

Sir Oliver Joseph Lodge.

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Lodge became assistant professor of applied mathematics at University College, London, in 1879 and was appointed to the chair of physics at University College, Liverpool, in 1881. During his tenure in Liverpool, he conducted experiments in the propagation and reception of electromagnetic waves. In 1890 a French physicist, Édouard Branly, showed that loose iron filings in a glass tube coalesce, or “cohere,” under the influence of radiated electric waves. To this basic design Lodge added a “trembler,” a device that shook the filings loose between waves. Connected to a receiving circuit, this improved coherer detected Morse code signals transmitted by radio wave and enabled them to be transcribed on paper by an inker. Lodge’s device, first demonstrated before the Royal Institute in 1894, quickly became the standard detector in early wireless telegraph receivers. It was outmoded the following decade by magnetic, electrolytic, and crystal detectors. Lodge also obtained patents in 1897 for the use of inductors and capacitors to adjust the frequency of wireless transmitters and receivers.

In 1900 Lodge was chosen the first principal of the new Birmingham University, and he was knighted in 1902. After 1900 he became prominent in psychical research, believing strongly in the possibility of communicating with the dead.

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...land stations. In 1900 also, Marconi filed his now-famous patent No. 7777 for Improvements in Apparatus for Wireless Telegraphy. The patent, based in part on earlier work in wireless telegraphy by Sir Oliver Lodge, enabled several stations to operate on different wavelengths without interference. (In 1943 the U.S. Supreme Court overturned patent No. 7777, indicating that Lodge, Nikola Tesla,...

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(1851-1940). British physicist Oliver Joseph Lodge was the exponent of psychic research, and an author; born in Penkhull, Staffordshire; did valuable foundation work in electricity and radio; principal of University of Birmingham 1900-19; in addition to autobiography and many scientific works, wrote Raymond, or Life and Death, and other books setting forth his belief in possibility of communication with the dead. Lodge died on August 22, 1940, in Lake, near Salisbury, Wiltshire, England.